I bet every car brand and model that has a cowl is subject to rust there, even Fords!!!! LOL... inside joke.
I will bet the cowl first, but some models tend to rust in windshield channel also. You might be thinking 68-70 B body.
I can pull the plastic guard off the top of cowl on the Volare and get my hand down in there, sorta , and feel the couple of rusted hole(s).
My early B bodies are bad about cowl rust in bottom and on the upper side. The 64 Savoy you put me onto (thanks again) will be fairly easy to address as the heater box will come out, and I will pull the instrument cluster to check out.
